1. Field of the Invention
This invention relates to the production of aqueous latices from solvent dispersions of high polymer compositions and aims generally to provide improved process and apparatus combinations therefor, and new products produced thereby.
2. Description of the Prior Art
To date, in the practical art, synthetic latices of high polymers have been primarily prepared by emulsion polymerization, and such practice has not been applicable to high polymers made by essentially anhydrous catalyst polymerizations. It has been proposed to prepare aqueous lactices of high polymers from solvent solutions thereof of processes of the type which comprise the general steps are (1) providing a dispersion or cement of the polymer in a volatile organic solvent for the polymer, (2) adding to such dispersion water and an aqueous emulsifier therefor and emulsifying the same to produce an emulsion, (3) stripping the volatile organic solvent from the said emulsion, and (4) recovering the resulting latex product. However, in the practical art difficulty has been experienced in attempting to render such proposed processes commercially feasable, inter alia, in that (1) solvent dispersions or cements of the high polymer materials, unless quite dilute, have high viscosities, which have rendered it impractical to produce raw emulsion particles of precursor latex particle size from such dispersions when their viscosities have been over 1000 to 7000 centipoises; and when dilute, require the use of undesirably high quantities of emulsifier and the stripping of undesirably large quantities of solvent; (2) in that the emulsions have tended to foam excessively during stripping; (3) in that the emulsions have tended to form coagulum by drying out especially on contact with heated surfaces, during the stripping and/or concentrating processes; and (4) in that all of these problems are accentuated as the aqueous content of the emulsion is reduced.